Propeller assembly



g- 15, 1967 c. w. VAN RANST 3,335,803

PROPELLER ASSEMBLY Filed June 13, 1966 2 Sheets-5heet 1 INVENTOR CORNELIUS W.\/ AN RAN-ST BWMM 15, 1967 c w. VAN RANST 3,335,803

PROPELLER AS 5 EMBLY Filed June 13, 1966 2 Sheets-5heet r;

INVENTOR CORNELIUS w. VAN RANST BY I and ATTORNEYS United States Patent 3,335,803 PROPELLER ASSEMBLY Cornelius W. Van Ranst, 15692 Woodland, Dearborn, Mich. 48120 Filed June 13, 1966, Ser. No. 557,227 1 Claim. (Cl. 170-13515 The present invention relates to a propeller assembly for use with motor boats, and more particularly, to such an assembly which includes a clutch mechanism to permit slippage of the propeller blades if an underwater obstruction is encountered by the blades.

It is an object of the present invention to provide a propeller assembly which has an improved construction and arrangement for allowing slippage of the propeller blades relative to the propeller shaft whenever an underwater obstruction is engaged by the blades.

It is another object of the present invention to provide an improved construction of the foregoing character which also permits axial flow of exhaust gases through the hub portion of the propeller assembly.

It is still another object of the present invention to provide an improved construction and arrangement of the foregoing character which permits relatively easy removal of the propeller assembly from the propeller shaft.

According to the present invention, one embodiment is provided which comprises an inner hub adapted to be connected to a propeller shaft for rotation therewith and having a rearwardly directed cone-shaped surface on its outer periphery, an outer hub with propeller blades radiating therefrom and having a cone-clutch surface on its inner periphery normally in engagement with the coneclutch surface of the inner hub, and a coil spring held in compression between annular shoulder members positioned respectively on the rearward outer surface of the inner hub and on the forward inner surface of the outer hub for urging the clutch surfaces into engagement and which is adapted to release said surfaces from clutching engagement in the event an underwater obstruction is engaged. I

In another embodiment of the present invention, an improved arrangement is provided for removing the propeller assembly from the propeller shaft of the type which has a taper on which the propeller assembly is mounted. In this form of the invention the outer hub of the propeller assembly has a collar on its inner surface adjacent to its rearward end adapted to cooperate with the nut for securing the propeller assembly on the shaft, whereby unscrewing of the nut will have the effect of pulling the outer hub from the propeller shaft. It is contemplated that the propeller assembly can be formed with any suitable means for. securing it to a propeller shaft, and it is also contemplated that the propeller assembly can provide an internal passage for flow of exhaust gases through the hub of the propeller assembly.

Other objects of this invention will appear in the following description and appended claim, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

In the drawings:

FIGURE 1 is a fragmentary sectional view taken on the line 11 of FIG. 2, showing a portion of a propeller shaft on which is supported the hub portion of a propeller assembly embodying the present invention;

FIGURE 2 is an end elevation of the embodiment shown in FIG. 1;

FIGURE 3 is a fragmentary sectional view taken on V 3,335,803 Patented Aug. 15, 1967 Before explaining the present invention in detail, it is to be understood that the invention is capable of other embodiments and of being practiced or carried out in various ways. It is also to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Referring now to the drawings, the embodiment of the invention illustrated in FIGS. 1 and 2 will be described. As shown, a propeller assembly 10 is supported on a propeller shaft 12. The latter is shown broken away at its outer end, but it will be understood that the shaft 12 will have a threaded end portion for receiving a nut (not shown) which will function to secure the propeller assembly in place on the shaft 12.

The propeller assembly 10 includes an inner hub 14 with a hollow bore for fitting onto the propeller shaft 12, and the rearward end of the hollow bore is splined, as at 16, for receiving the corresponding splines 18 of the propeller shaft 12 so that the inner hub 14 will always rotate with the propeller shaft 12. The outer surface of the inner hub 14 defines at its forward end a rearwardly facing or rearwardly directed cone-clutch surface 20. Rearwardly of the cone-clutch surface 20 is an annular groove 22 in which is seated a retaining ring 24 for a purpose to be described.

Fitted onto the inner hub 14 is an outer hub 26 which comprises two spaced coaxial sleeves 28 and 30 which are joined together by the spider or radial arms 32. Integrally connected to and projecting radially outwardly from the outer sleeve 30 are a plurality of propeller blades 34.

The outer hub 26 has formed on its inner periphery a cone-clutch surface 36 which is shaped and adapted to fit against the cone-clutch surface 20 for frictionally locking these surfaces together during normal operation of the propeller assembly 10, thereby assuring that the propeller blades 34 will rotate with the propeller shaft 12. Immediately adjacent to the rearward end of the cone-clutch surface 36 is an annular shoulder 38 which is adapted to cooperate with the annual shoulder 24 on the inner hub 14 for normally maintaining the cone-clutch surfaces 20 and 36 in frictional engagement so as to assure proper rotation of the propeller blades 34 with the propeller shaft 12. Supported between the inner hub 114 and outer hub 26 is a compression spring 40 which urges the washers 42 and 44, and thereby the annular shoulder rnembers 24 and 38, axially apart, so as to hold the clutch mechanism in the locked position shown in FIG. 1.

In the event the propeller blades 34 should strike an underwater object the force of such a blow will overcome the forces of the coil spring 40 and will permit the clutch surface 36 to be moved rearwardly so as to move out of engagement with the clutch surface 20. This will have the effect of permitting the shaft 12 to continue to rotate while allowing the propeller blades 34 to discontinue such rotation until they have become disengaged from the underwater obstruction. This in turn will prevent unnecessary damage or breakage of the propeller assembly. As soon as the underwater obstruction has been cleared, the compression spring 40' will again urge the outer hub 26 forward, so that the cone-clutch surfaces 20 and 36 reengage, after which the propeller blades 34 will again rotate with the propeller shaft 12.

The embodiment of the invention illustrated in FIGS. 1 and 2 is constructed and arranged so that exhaust gases can flow through the propeller assembly around the inner hub 14 and between the inner and outer sleeve members 28 and 30. It is also constructed and arranged so that the propeller shaft 12 can be of a construction wherein there is no taper at the end of the propeller shaft 12, whereby the propeller assembly 10 may readily be removed from the shaft 12 merely by removing the securing nut, not shown, and thereafter, pulling the propeller assembly rearwardly olf of the splined end 18 of the propeller shaft 12. It is to be understood, however, that the present invention is not limited to these particular details of construction, and attention is next directed to the embodiment of the invention illustrated in FIGS. 3 and 4, wherein other details of construction which come within the scope of the present invention are disclosed.

As shown in FIGS. 3 and 4, a propeller assembly 50 is provided which is mounted on a propeller shaft 52 which has a tapered end-portion 54 terminating in a threaded end 56 which has .a terminal end-portion 58 for a purpose to be described. The propeller assembly 50 includes an inner hub 60 which has a similar outer surface to that of inner hub 14, in that it has a cone-clutch surface 62 which is rearwardly faced or directed, and it has an annular shoulder member 64 seated thereon. However, it will be observed that the inner periphery of the inner hub 60 is tapered at 66 to accommodate the taper 54 on the end of the propeller shaft 52, and a conventional keyway 68 is provided therein for receiving the key 70 for locking the propeller assembly 50 for rotation with the propeller shaft 52. The propeller assembly 50 is secured in place on the propeller shaft 52 by means of the nut 72, jam nut 74, and the cotter pin 76 which extends through the terminal end portion 58.

Supported on the inner hub 60 is an outer hub 78 which has a plurality of propeller blades 80 radiating therefrom and which have an inner periphery containing a cone-clutch surface 82 adapted to engage frictionally and fit against the cone-clutch surface 62. Also on the inner periphery of the outer hub 78 is an annular shoulder 84 which is adapted to cooperate with the annular shoulder 64 of the inner hub member 60 for holding coil spring 86 in a state of compression so as to provide a mechanism for normally holding the cone-clutch surfaces 62 and 82 in frictional engagement, whereby the propeller blades will rotate with the propeller shaft 52. However, if an obstruction is encountered by the propeller blades 80, the blades will be moved axially rearwardly with respect to the propeller shaft 52 so as to release the engagement between the clutching surfaces 62 and 82, thereby permitting slippage of the blades relative to the shaft 52. This will assure minimum damage to the propeller blades 80 as a result of their encountering such an obstruction.

It will be observed that the embodiment of the invention shown in FIGS. 3 and 4 is constructed and arranged so that there is no passage through the hub of the propeller assembly, such as is provided in the embodiment of the FIGS. 1 and 2. Another distinguishing feature found in the embodimenn in FIGS. 3 and 4 is the arrangement for removing the propeller assembly 50 from the propeller shaft 52, should this be necessary. As will be recognized by those skilled in the art, it is normally necessary to use a conventional wheel pulling device for removing a propeller asesmbly from a propeller shaft when a tapered shaft, of the type illustrated in FIG. 3, is employed. In this situation, it is a common occurrence that the propeller assembly will adhere very tightly to the tapered shaft, and it then is necessary to use a convention pulling device to remove the propeller assembly therefrom. The present invention provides a feature whereby the propeller assembly 50 can be readily removed without employment of a separate wheel pulling device. For this purpose, the outer hub member 78 is provided with a groove 88 in which is seated a retaining ring 90. The latter is located so that it will be engaged by the annular collar 92 that is provided on the nut 72.

Thus, when it is desired to remove the propeller assembly 50 from the propeller shaft 52, the normal procedure will be to remove the cotter pin 76, remove the jam nut 74, and thereafter unscrew the nut 72. When the annular collar 92 engages the retaining ring 90, a force will be exerted on the outer hub 78 in an axially rearward direction so as to move the latter out of clutching engagement with the inner hub 60, and such movement will continue to occur until the compression spring 86 is fully compressed between the annular shoulder members 64 and 84. Thereafter, when the nut 72 is further unscrewed, the inner hub 60 will also be moved in a rearward direction, thereby breaking the holding action that may have developed between the tapered surfaces 54 and 66. It is recognized that in some instances this holding action will be very great, and for this purpose, the terminal end 58 is provided which has a reduced diameter from the threaded end-portion of the propeller shaft 52 to permit the terminal end portion 58 to be struck to aid in breaking the holding action between the tapered surfaces 54 and 66 so that the propeller assembly 50 can be released from the propeller shaft 52.

From the foregoing description, it will be recognized that an improved propeller assembly has been provided which is constructed and arranged to minimize the damage that can occur to the propeller blades in the event a water obstruction is encountered, and a propeller assembly is provided which can readily be removed in all instances from the propeller shaft on which the propeller assembly is mounted.

I claim:

In combination, a tapered propeller shaft having a threaded end portion, a propeller assembly comprising an inner hub with an internal tapered portion secured on said shaft for rotation therewith, said inner hub having a rearwardly directed cone-clutch surface on its outer periphery, an outer hub with propeller blades radiating therefrom and having a cone-clutch surface on its inner periphery normally in engagement with the cone-clutch surface of the inner hub, annular shoulder members positioned respectfully on the rearward outer surface of the inner hub and on the forward inner surface of the outer hub, spring means operably disposed between said annular shoulder members for urging the outer hub into clutching engagement with the inner hub, said outer hub having a collar member on its rearward end projecting radially inwardly, and a nut threadedly secured to the threaded portion of said shaft and having projections extending radially outwardly and located axially forward of said collar member and engageable with said collar member when the nut is unscrewed from said shaft, said threaded end portion having an axial projection of reduced diameter for receiving blows from a hammer or the like when said nut is being unscrewed from said shaft.

References Cited UNITED STATES PATENTS 1,472,077 10/ 1923 Lockwood. 1,482,498 2/ 1924 Wills. 2,515,303 7/1950 Isnard. 2,569,144 9/1951 Benson. 2,642,730 6/1953 Snyder 135.75 X 3,092,185 6/1963 Alexander 170135.71 3,232,186 2/1966 Garrett et al. 170173 X 3,246,698 4/ 1966 Kiekhaefer.

MARTIN P. SCHWADRON, Primary Examiner. EVERETTE A. POWELL, JR.) Examiner, 

